SIP Trunk with 3CX

Setting Up the Virtual-Call SIP Trunk in a 3CX

The following provides a step-by-step configuration of the 3CX phone system with Virtual-Call SIP trunking.

For detailed information about configuring the 3CX system regarding extensions, number routing, rules, etc., please consult the 3CX documentation.

1. In the 3CX management console, click on SIP Trunks.
2. Click on "Add SIP Trunk".
   
   
    
3. In the menu, select "Generic" as the country.
4. As "Country-specific provider", select "Generic SIP Trunk".
5. Under Main trunk number, enter your main number in the format 4922112345670.
6. Confirm the dialog by clicking OK.
   
   
    
7. Under Trunk, enter "Virtual-Call".
8. Under Registrar, enter "trunk.virtual-call.net". You can adjust port 5060 to suit your network if necessary. Please consult your local network administrator for this.
9. Leave the outbound proxy empty.
10. As authentication type, select "Registration/Account based".
11. As authentication ID, enter the account ID of the user (main number) from your customer account.
12. The authentication password is shown in your customer account under the respective user (SIP password).
    
    
     
13. Confirm the changes by clicking OK. On the following page, a green dot indicates a successful registration of your 3CX system with our server.
    
    
     
14. The displayed outgoing caller ID can be configured in the 3CX phone system in various places, for example per extension or per trunk. For more information, please refer to the 3CX documentation.
    At Virtual-Call, the outgoing caller ID is set via the FROM field. Please ensure correct configuration of the parameters in the SIP Trunk under "Outbound parameters". The ideal setting depends on your phone system configuration.
    
    The recommended setting is "Outbound Caller ID". This displays the number you have specified as the outgoing number in the respective extension.
    With "Custom Field", you can assign a fixed outgoing number for the entire trunk.
    
    
     
15. To add additional phone numbers, select "SIP Trunks" from the menu.
16. Double-click on the Generic SIP Trunk you just created.
    
    
     
17. Click on DIDs.
18. Select "Add DID".
19. Enter the additional phone numbers from your customer account in the format 4922112345671.
20. Click OK.
    
    
     
21. Click on "Inbound parameters".
22. In the dropdown menu "CallerNum", select "To: User Part".

Your 3CX phone system is now configured for incoming and outgoing calls. You can now configure call routing within the system to different extensions according to the manufacturer's manual.

If you experience NAT problems (one-way audio, one party cannot hear the other), the following article may help: https://www.3cx.com/blog/voip-howto/firewall-nat-pat-stun/

Further information: https://www.3cx.de/voip-sip/nat/